Damping device and furniture part comprising the same

ABSTRACT

A damping device includes a housing, a piston and a controller. The housing defines a chamber filled with a damping medium. The piston is movable in the chamber and includes a passage for allowing the damping medium to pass through. The controller includes a control member and a resilient member. The control member is capable of being moved toward the passage of the piston or closing a portion or all portions of the passage of the piston in response to a speed of the piston.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a damping device, and moreparticularly, to a damping device adapted to a movable furniture part.

2. Description of the Prior Art

US patent with Patent No. U.S. Pat. No. 8,181,758 B2 discloses a dampingdevice including a cylinder (10). The cylinder (10) is filled with adamping medium. A resilient member (20) is disposed in the cylinder (10)and a piston (40) is movably mounted in the cylinder (10). The piston(40) includes a piston body (42), a connection portion (44) connected toan end of the resilient member (20) and a neck portion (46) connectedbetween the piston body (42) and the connection portion (44). A controlvalve (60) is movably mounted to the neck portion (46) of the piston(40), wherein the control valve (60) is able to control a travelingvelocity of the piston (40) by closing or detaching from openings withrespect to the piston body (42).

The damping device disclosed in the US patent with Patent No. U.S. Pat.No. 8,181,758 B2 can be implemented in a wide range of use, for example,a drawer slide rail assembly of a furniture or a server slide railassembly of a rack system. The said slide rail assemblies have functionsof push-open and/or self-close. Herein, the damping device facilitatesdecreasing a retracting speed by which the slide rail assembly (or adrawer) moves during a final step of process where the slide rail (orthe drawer) moves from an extended state (or an open state) to aretracted state (or a closed state) relative to another slide rail (or acabinet body). For example, US patent with Patent No. U.S. Pat. No.8,172,345 B2 discovers a so-called push-open mechanism that facilitatesthe drawer, as being in a closed position, to be opened relative to thecabinet body by the drawer being pushed, and a so-called self-closemechanism that facilitates the drawer to be closed by itself during thefinal step of a process where the drawer is moved from an open positionto a closed position. In addition, US patent with Patent No. U.S. Pat.No. 8,308,251 B2 discovers a design where intensity of push-openmechanism can be adjusted. The said three patents are incorporatedherein for references.

However, when force exerted by users to close the drawer from an openposition is excessive, or when the force is continuously applied as thedrawer reaches the cabinet body, the drawer may pass the closed positionof the cabinet body to an over-pressed position. As a result, the drawerwill be re-opened by the push-open mechanism, resulting in failure ofthe drawer being closed relative to the cabinet. The present inventionis provided to improve the abovementioned issues.

SUMMARY OF THE INVENTION

The present invention provides a damping device capable of generating adamping force in response to an exerted external force.

According to an aspect of the present invention, a damping deviceincludes a housing, a piston and a controller. The housing has an innerwall, and a chamber is defined by the inner wall. The chamber has adamping medium filled therewith. The piston is movable in the chamber ofthe housing and includes at least one passage for allowing the dampingmedium to pass through. The controller is arranged in the chamber of thehousing and includes a control member and a resilient member. When thepiston is moved relative to the housing by a damping speed, the controlmember is moved toward the passage of the piston or closes a portion orall portions of the passage of the piston in response to the dampingspeed. When the control member closes the portion or the all portions ofthe passage of the piston, the control member is capable of controllingan amount of the damping medium passing through the passage of thepiston.

Preferably, the resilient member generates a resilient force to thecontrol member in response to the damping speed.

Preferably, the damping device further includes a base movable in thechamber, and the controller is disposed between the piston and the base,wherein the base is connected to the piston via an extending portion,and the controller is movably mounted on the extending portion.

Preferably, the piston is moved in the chamber of the housing in asubstantially linear direction.

Preferably, the resilient member is a disc spring.

Preferably, the control member defines a space, and the space is foraccommodating the resilient member.

Preferably, the piston includes a connecting portion and a contactingportion. The connecting portion and the contacting portion are spaced bya step difference. The base is connected to the connecting portion ofthe piston via the extending portion, and the resilient member deformselastically through the step difference.

Preferably, the control member and the resilient member are integrallyformed as a part.

Preferably, the control member and the resilient member are separateparts.

Preferably, the damping device further includes a spring for providingan elastic force to one of the piston and the base.

Preferably, the inner wall has a first inner diameter and a second innerdiameter from a top portion to a bottom portion of the housing, and thefirst inner diameter is greater than the second inner diameter.

Preferably, the inner wall has the first inner diameter, the secondinner diameter and a third inner diameter from the top portion to thebottom portion of the housing, and the second inner diameter is greaterthan the third inner diameter.

Preferably, the inner wall has the first inner diameter, the secondinner diameter and a third inner diameter from the top to the bottom ofthe housing, and the third inner diameter is greater than the secondinner diameter.

According to another aspect of the present invention, a damping deviceincludes a housing, a piston, a base and a controller. The housingdefines a chamber, and the chamber has a damping medium filledtherewith. The piston is movable in the chamber. The base is movable inthe chamber with the piston. Both of the base and the piston include apassage respectively for allowing the damping medium to pass through.The controller is located between the passage of the base and thepassage of the piston.

According to another aspect of the present invention, a furniture partincluding a first furniture member, a second furniture member, anejection device, a retraction device and a damping device is provided.The ejection device is configured to provide an opening force for thesecond furniture to be moved in a second direction, which is opposite toa first direction, to a third position in response to the opening forcewhen the second furniture member is moved relative to the firstfurniture from a first position to a second position in the firstdirection. The retraction device provides a closing force for the secondfurniture member to be moved toward the first position during a finalstep where the second furniture member is moved relative to the firstfurniture member from the third position close to the first position inthe first direction. The damping device is configured to provide adamping effect during a process where the second furniture member ismoved toward the first position in response to the closing force. Thedamping device includes a housing, a piston, a base and a controller.The housing defines a chamber, and the chamber has a damping mediumfilled therewith. The piston is movable in the chamber and includes apassage for allowing the damping medium to pass through. The base ismovable in the chamber. The controller is located between the piston andthe base and includes a control member and a resilient member, whereinthe control member is configured to close a portion or all portions ofthe passage of the piston. The resilient member is configured to providea resilient force for the control member to no longer close the passageof the piston.

These and other objectives of the present invention will no doubt becomeobvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiment that isillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective diagram of the damping device according to afirst embodiment of the present invention.

FIG. 2 is an exploded diagram of the damping device according to thefirst embodiment of the present invention.

FIG. 3 is a half-section view of the damping device according to thefirst embodiment of the present invention.

FIG. 4 is an enlarged drawing of the zone A shown in FIG. 3.

FIG. 5 is an internal diagram of the damping device according to thefirst embodiment of the present invention.

FIG. 6 is an enlarged drawing of the zone A shown in FIG. 5.

FIG. 7 is a diagram showing that one of a piston and a housing of thedamping device is able to be displaced due to a force according to thefirst embodiment of the present invention.

FIG. 8 is an enlarged drawing of the zone A shown in FIG. 7.

FIG. 9 is a diagram showing a control member closing a passage of thepiston of the damping device according to the first embodiment of thepresent invention.

FIG. 10 is an enlarged drawing of the zone A shown in FIG. 9.

FIG. 11 is a diagram showing that the control member of the dampingdevice no longer closes the passage of the piston according to the firstembodiment of the present invention.

FIG. 12 is an enlarged drawing of the zone A shown in FIG. 11.

FIG. 13 is a diagram of a damping device with a piston being forcedaccording to a second embodiment of the present invention.

FIG. 14 is a diagram of the damping device with the piston not beingforced according to the second embodiment of the present invention.

FIG. 15 is a diagram of a damping device with a controller not closing apassage of a piston according to a third embodiment of the presentinvention.

FIG. 16 is a diagram of the damping device with the controller closingthe passage of the piston according to the third embodiment of thepresent invention.

FIG. 17 is a diagram of a damping device with a controller not closing apassage of a piston according to a fourth embodiment of the presentinvention.

FIG. 18 is a diagram of the damping device with the controller closingthe passage of the piston according to the fourth embodiment of thepresent invention.

FIG. 19 is a diagram of a damping device with a controller not closing apassage of a piston according to a fifth embodiment of the presentinvention.

FIG. 20 is a diagram of the damping device with the controller closingthe passage of the piston according to the fifth embodiment of thepresent invention.

FIG. 21 is an internal diagram of a damping device according to a sixthembodiment of the present invention.

FIG. 22 is a diagram showing that the damping device is applied to afurniture part and a second furniture member is in the first positionrelative to a first furniture member according to the first embodimentof the present invention.

FIG. 23 is a diagram of the second furniture member being located in asecond position relative to the first furniture member according to thefirst embodiment of the present invention.

FIG. 24 is a diagram of the second furniture member being located in athird position relative to the first furniture member according to thefirst embodiment of the present invention.

FIG. 25 is a diagram of a damping force provided by the damping deviceunder a first condition according to the first embodiment of the presentinvention.

FIG. 26 is a diagram of the damping force provided by the damping deviceunder a second condition according to the first embodiment of thepresent invention.

FIG. 27 is a diagram of the damping force provided by the damping deviceunder a third condition according to the first embodiment of the presentinvention.

DETAILED DESCRIPTION

FIG. 1 to FIG. 3 are diagrams illustrating a damping device 20 accordingto a first embodiment of the present invention. The damping device 20includes a housing 22, a piston 24, a base 28, a control member 30 and aresilient member 32. Preferably, the damping device 20 further includesan extending member 26 and a spring 34.

The housing 22 has an inner wall 38, and a chamber 36 is defined by theinner wall 38. The housing 22 includes a bottom portion 40 and a topportion 42. Preferably, the bottom portion 40 is a closed end, and thetop portion 42 has an opening 44 communicating with the chamber 36.Besides, the damping device 20 further includes a cover 46 configured toclose the opening 44.

The piston 24 is movable in the chamber 36. Specifically, the piston 24is moved in the chamber 36 of the housing 22 in a substantially lineardirection. On the other hand, the extending member 26 is movablerelative to the housing 22 via the piston 24. Specifically, one end ofthe extending member 26 is connected to a first side 24 a of the piston24, and another end of the extending member 26 passes through the cover46 and partially extends out of the chamber 36.

The base 28 can be moved in the chamber 36 with the piston 24.Preferably, the base 28 is connected to a second side 24 b of the piston24, wherein the second side 24 b is opposite to the first side 24 a.Besides, the base 28 and/or the piston 24 include at least one passage.Hereinafter, the base 28 and the piston 24 respectively including aplurality of passages 48 and a plurality of passages 50 are illustrativeof an example, as shown in FIG. 2, but the present invention is notlimited thereto.

The control member 30 and the resilient member 32 can be deemed as acontroller. Specifically, the control member 30 and the resilient member32 are located between the piston 24 and the base 28. In the presentembodiment, the control member 30 and the resilient member 32 are twoseparate parts. Preferably, the control member 30 defines a space 33,and the space 33 is configured to accommodate the resilient member 32.The control member 30 and the resilient member 32 are movable betweenthe base 28 and the piston 24. Hereinafter, the resilient member 32, forexample, is a disc spring, but it is not limited thereto.

The spring 34 is configured to provide an elastic force to the piston24. Hereinafter, the spring 34 providing the elastic force to the piston24 via the base 28 is illustrative of an example. In other words, theelastic force generated by the spring 34 is exerted to the piston 24 andthe base 28.

As shown in FIG. 4, the base 28 is connected to the piston 24 via anextending portion 52, wherein the control member 30 and the resilientmember 32 are movably mounted to the extending portion 52.

As shown in FIG. 5 and FIG. 6, the piston 24 and the housing 22 are in apre-damping state. At this time, the piston 24 and the chamber 36between the piston 24 and the top portion 42 of the housing 22 define afirst zone R1, and the piston 24 and the chamber 36 between the piston24 and the bottom portion 40 of the housing 22 define a second zone R2.The extending member 26 is able to partially extend out of the chamber36 of the housing 22 rapidly by the elastic force generated by thespring 34. Moreover, the chamber 36 of the housing 22 is filled with adamping medium. The said damping medium includes a fluid (the dampingmedium is illustrated as a plurality of black dots in FIG. 5 and FIG.6). The passages 50 of the piston 24 and the passages 48 of the base 28are configured to allow the damping medium to pass through. The controlmember 30 and the resilient member 32 are located between passageopenings E1 of the passages 48 of the base 28 and passage openings E2 ofthe passages 50 of the piston 24.

The inner wall 38 of the housing 22 has a first inner diameter S1 and asecond inner diameter S2 from the top portion 42 to the bottom portion40 of the housing 22. Preferably, the inner wall 38 further has a thirdinner diameter S3. In the present embodiment, the inner wall 38 of thehousing 22 has the first inner diameter S1, the second inner diameter S2and the third inner diameter S3 arranged in order from the top portion42 to the bottom portion 40 of the housing 22, wherein the first innerdiameter S1 is greater than the second inner diameter S2, and the secondinner diameter S2 is greater than the third inner diameter S3. It isnoticed that the housing 22 has a frontal section 220, a middle section221 and an end section 222 in order from the top portion 42 to thebottom portion 40 of the housing 22. As shown in FIG. 5, the inner wall38 has the first inner diameter S1 located corresponding to the frontalsection 220, the inner wall 38 has the second inner diameter S2 locatedcorresponding to the middle section 221, and the inner wall 38 has thethird inner diameter S3 located corresponding to the end section 222,respectively. According to the arrangement, the damping device 20 iscapable of providing a damping effect with a substantially gradualincrement along the frontal section 220, the middle section 221 and theend section 222 of the housing 22. Further, the inner wall 38 of thefrontal section 220 and the inner wall 38 of the end section 222 areboth cylindrical surfaces, and the inner wall 38 of the middle section221 is a truncated cone surface. The truncated cone surface (i.e. theinner wall 38 of the middle section 221) is connected to both of thecylindrical surfaces (i.e. the inner wall 38 of the frontal section 220and the inner wall 38 of the end section 222). Thereby, the dampingdevice 20 is capable of providing a first constant damping effect in thefrontal section 220 and a second constant damping effect in the endsection 222. Besides, the damping device 20 is capable of providing thedamping effect with the substantially gradual increment in the middlesection 221. Besides, the housing 22 has an outer diameter OD, and theouter diameter OD of the housing 22 retains a constant value from thetop portion 42 to the bottom portion 40 of the housing 22. That is, theouter diameter OD corresponding to the frontal section 220, the outerdiameter OD corresponding to the middle section 221 and the outerdiameter OD corresponding to the end section 222 are equal to oneanother. The arrangement where the outer diameter OD of the housing 22retains the constant value from the top portion 42 to the bottom portion40 of the housing 22 ensures the damping device 20 not to require anextra externally mechanical space, so that the damping device 20 is ableto be implemented to the same apparatus (for example, the furniturepart) due to no requirement of the extra externally mechanical space.

In addition, the base 28 is connected to the second side 24 b of thepiston 24 via the extending portion 52. On the other hand, the controlmember 30 and the resilient member 32 are movable between the passages48 of the base 28 and the passages 50 of the piston 24 along theextending portion 52. Besides, the passages 50 of the piston 24communicate with the first side 24 a and the second side 24 b of thepiston 24.

As shown in FIG. 7 and FIG. 8, when the piston 24 is moved relative tothe housing 22 by a damping speed, for example, one of the piston 24 andthe housing 22 is displaced relative to the other one of the piston 24and the housing 22, the damping device 20 is able to provide a dampingeffect. The damping effect provided by the damping device 20 can bevarious according to different conditions. In the present embodiment, itis illustrative of an example that the piston 24 receiving a force (oran external force) via the extending member 26 to move the piston 24relative to the housing 22.

In the first condition, for example, a first force F1 is exerted to theextending member 26 or the piston 24 and causes the extending member 26or the piston 24 to generate a first speed, and the piston 24 can passthrough the chamber 36 defined by the first inner diameter S1, thesecond inner diameter S2 and the third inner diameter S3 in order (FIG.7 and FIG. 8 only illustrate the piston 24 being located in the endsection of the interior of the chamber 36 defined by the second innerdiameter S2). During the process, the damping medium in the second zoneR2 (the damping medium is illustrated as a plurality of black dots inFIG. 7 and FIG. 8) flows towards the said first zone R1 in response tothe first force F1 and generates a first corresponding force F1′.Specifically, the fluid of the damping medium can flow from a zone ofthe second side 24 b of the piston 24 to a zone of the first side 24 aof the piston 24, so as to generate the first corresponding force F1′.Hereinafter, the fluid of the damping medium can flow out from thepassage openings E1 of the passages 48 of the base 28, and then reachesthe zone of the first side 24 a of the piston 24 through the passages 50of the piston 24 and a clearance between the peripheral of the piston 24and the inner wall 38 of the housing 22, respectively. The controlmember 30 and the resilient member 32 can be driven by the firstcorresponding force F1′ and taken away from the passage openings E1 ofthe base 28 to approach the passage openings E2 of the piston 24, so asto control the flow rate of the damping medium from the second side 24 bto the first side 24 a through the passages 50 of the piston 24. Inother words, the control member 30 is capable of being moved towards thepassages 50 of the piston 24 according to the damping speed. Herein, theresilient member 32 generates a resilient force in response to thedamping speed. For example, the resilient member 32 can be moved to abutagainst a surface 55 of the second side 24 b of the piston 24. Thereby,the damping device 20 is able to provide a first damping effect inresponse to the first condition. Herein, the spring 34 accumulates anelastic force in response to the displacement of the piston 24. When theelastic force is released, the elastic force is configured to recoverthe piston 24 and the housing 22 to the pre-damping state shown in theFIG. 5.

As shown in FIG. 9 and FIG. 10, in the second condition, for example, asecond force F2 is exerted to the extending member 26 or the piston 24and causes the extending member 26 or the piston 24 to generate a secondspeed, and the second speed is greater than the first speed. The piston24 can pass through the chamber 36 defined by the first inner diameterS1, the second inner diameter S2 and the third inner diameter S3 inorder (FIG. 9 and FIG. 10 only illustrate the piston 24 being located inthe chamber 36 defined by the third inner diameter S3). At this time,the damping medium (the damping medium is illustrated as a plurality ofblack dots in FIG. 9 and FIG. 10) generates a second corresponding forceF2′ in response to the second force F2 and against the second force F2.Specifically, the fluid of the damping medium flows from the zone of thesecond side 24 b of the piston 24 to the zone of first side 24 a of thepiston 24 for generating the second corresponding force F2′. Herein, thesecond corresponding force F2′ is able to drive the control member 30and the resilient member 32 to depart from the passage openings E1 ofthe base 28 and approach the passage openings E2 of the piston 24.Preferably, the control member 30 is located in a predetermined positionX adjacent to the second side 24 b of the piston 24 in response to thesecond corresponding force F2′, such that the control member 30 is ableto close a portion or all portions of the passages 50 of the piston 24,so as to control the flow rate of the damping medium passing through thepassages 50 of the piston 24 to increase the damping force. Theresilient member 32 is located in the predetermined position X inresponse to the control member 30 and accumulates a resilient force F3.That is, the control member 30 can close the portion or the all portionsof the passages 50 of the piston 24 according to the damping speed, soas to control the flow rate of the damping medium passing through thepassages 50 of the piston 24. For example, when the second correspondingforce F2′ is exerted to the control member 30 which has closed thepassages 50 of the piston 24, the flow rate of the damping mediumpassing through the passages 50 of the piston 24 from the zone of thesecond side 24 b of the piston 24 to the zone of the first side 24 a ofthe piston 24 will be reduced or cut off. Therefore, when the controlmember 30 closes the passages 50 of the piston 24 and the fluid of thedamping medium flows out from the passage openings E1 of the passages 48of the base 28, the fluid of the damping medium reaches the zone of thefirst side 24 a of the piston 24 through the clearance between theperipheral of the piston 24 and the inner wall 38 of the housing 22,which results in a significant damping force. On the other hand, theresilient member 32 deforms elastically due to abutting against thesurface 55 of the piston 24 and accumulates the resilient force F3.Thereby, it is known that the damping device 20 can provide a seconddamping effect according to the second condition.

In a third condition or in a pre-damping condition, when the piston 24is located in the chamber 36 defined by the first inner diameter S1, thesecond inner diameter S2 and the third inner diameter S3 (FIG. 9 andFIG. 10 only illustrate the piston 24 being located in the chamber 36defined by the third inner diameter S3) and the second force F2 isexerted to the piston 24 (in the third condition, the second force F2 isan impulse or a sudden excessive force), similar to the secondcondition, the control member 30 is capable of closing at least theportion or all portions of the passages 50 of the piston 24 in responseto the second corresponding force F2′ to increase the damping force, andthe resilient member 32 accumulates the resilient force F3. As shown inFIG. 10, FIG. 11 and FIG. 12, once a speed of the second force F2exerted to the piston 24 or the extending member 26 is decreased to acertain degree by the said increased damping force, or the second forceF2 decreases less than the resilient force F3 accumulated by theresilient member 32, the resilient member 32 will release the resilientforce F3 and the resilient force F3 is exerted to the control member 30,such that the control member 30 is moved away from the predeterminedposition X and no longer close the passages 50 of the piston 24.Thereby, the damping device 20 provides a weaker damping force inresponse to the third condition changing from the second damping effect.That is, the damping device 20 is able to provide a variable dampingeffect.

FIG. 13 and FIG. 14 are diagrams illustrating a damping device 200according to a second embodiment of the present invention. Specifically,a major difference between the damping device 200 according to thesecond embodiment and the damping device 20 according to the firstembodiment is that the said spring 34 is omitted in the damping device200. Furthermore, a chamber 204 in a housing 202 of the damping device200 is filled with a damping medium. The said damping medium includes afluid (the damping medium is illustrated as a plurality of black dots inFIG. 13 and FIG. 14). The chamber 204 is pressurized in advance. When anextending member 206 or a piston 208 receives a force F4 (or an externalforce), a control member 210 is capable of closing a portion or allportions of passages 212 of the piston 208. Once the force F4 stops, apressure in the chamber 204 is able to drive the fluid of the dampingmedium to gradually activate the piston 208, leading the piston 208 andthe housing 202 to recover to the pre-damping state (as shown in FIG.14).

FIG. 15 and FIG. 16 are diagrams illustrating a damping device 300according to a third embodiment of the present invention. Specifically,a major difference between the damping device 300 according to the thirdembodiment and the damping devices 20, 200 according to the first andthe second embodiment respectively is that a resilient member 302 is aflat sheet and a second side 306 of a piston 304 includes a connectingportion 308 and a contacting portion 310. A surface 312 of theconnecting portion 308 and the contacting portion 310 are spaced by astep difference H. Furthermore, a base 314 is connected to theconnecting portion 308 of the piston 304 via an extending portion 316.On the other hand, a control member 318 and the resilient member 302 aremovable between passages 320 of the base 314 and passages 322 of thepiston 304 along the extending portion 316. When the extending member324 or the piston 304 receives a force F5 (or an external force), in apre-damping state, the control member 318 is capable of abutting againstthe contacting portion 310 of the piston 304 in response to acorresponding force K of a fluid of a damping medium, so as to close aportion or all portions of the passages 322 of the piston 304 forcontrolling a flow rate of the damping medium passing through thepassages 322 of the piston 304. Thus, the damping force increasesaccordingly. The resilient member 302 abuts against the surface 312 ofthe connecting portion 308 of the piston 304 and deforms elasticallythrough the step difference H, so as to accumulate a resilient force.When the force F5 decreases and the resilient member 302 releases theresilient force, the control member 318 no longer closes the passages322 of the piston 304.

FIG. 17 and FIG. 18 are diagrams illustrating a damping device 400according to a fourth embodiment of the present invention. Specifically,a major difference between the damping device 400 according to thefourth embodiment and the damping devices 20, 200, 300 according to thefirst, the second and the third embodiment respectively is that acontrol member 402 and a resilient member 404 are integrally formed as apart. Moreover, an appearance of a controller formed by the controlmember 402 and the resilient member 404 is a disc spring. A concaveportion 406 is defined between the resilient member 404 and the controlmember 402. When an extending member 408 or a piston 410 receives aforce F6 (or an external force), in a pre-damping condition, the controlmember 402 is capable of abutting against a contacting portion 412 ofthe piston 410 in response to a corresponding force K of a fluid of adamping medium, so as to close a portion or all portions of passages 414of the piston 410 for controlling a flow rate of the damping mediumpassing through the passages 414 of the piston 410. Thus, a dampingforce increases accordingly. The resilient member 404 abuts against asurface 418 of a connecting portion of the piston 410, so as to providea resilient force. When the force F6 decreases and the resilient member404 releases the resilient force, the control member 402 no longercloses the passages 414 of the piston 410. It is noticed that theconcave portion 406 facilitates the corresponding force K of the fluidof the damping medium to drive the control member 402 for closing thepassages 414 of the piston 410.

FIG. 19 and FIG. 20 are diagrams illustrating a damping device 500according to a fifth embodiment of the present invention. Specifically,a major difference between the damping device 500 according to the fifthembodiment and the damping device 400 according to the fourth embodimentis that no concave portion 406 is defined between the resilient member404 and the control member 402. Specifically, a side 504 of a controlmember 502 is a plane. Therefore, when an extending member 506 or apiston 508 receives a force F7 (or an external force), in a pre-dampingcondition, the control member 502 is capable of receiving acorresponding force K of a fluid of a damping medium through the side504, so as to close a portion or all portions of passages 510 of thepiston 508. Namely, this embodiment is able to provide the functionsmentioned above.

FIG. 21 is a diagram illustrating a damping device 600 according to asixth embodiment of the present invention. Specifically, a majordifference between the damping device 600 according to the sixthembodiment and the damping devices according to the first to the fifthembodiments is that an inner wall 604 of a housing 602 has a first innerdiameter S4, a second inner diameter S5 and a third inner diameter S6arranged in order from a top portion 606 to a bottom portion 608 of thehousing 602, wherein the first inner diameter S4 is greater than thesecond inner diameter S5, and the third inner diameter S6 is greaterthan the second inner diameter S5. It is noticed that the housing 602has a frontal section 609, a middle section 610 and an end section 611in order from the top portion 606 to the bottom portion 608 of thehousing 602. As shown in FIG. 21, the inner wall 604 has the first innerdiameter S4 located corresponding to the frontal section 609, the innerwall 604 has the second inner diameter S5 located corresponding to themiddle section 610, and the inner wall 604 has the third inner diameterS6 located corresponding to the end section 611, respectively. Accordingto the arrangement, the damping device 600 is capable of providing anon-gradual damping effect along the frontal section 609, the middlesection 610 and the end section 611 of the housing 602 substantially.Further, the inner wall 604 of the frontal section 609, the inner wall604 of the middle section 610 and the inner wall 604 of the end section611 are connected to one another to form a camber. A vertex of thecamber is located on the inner wall 604 of the middle section 610, andthe second inner diameter S5 of the inner wall 604 of the middle section610 is a distance between two opposite vertices on a cross-section ofthe inner wall 604 of the middle section 610. Besides, the housing 602has an outer diameter OD, and the outer diameter OD of the housing 602retains a constant value from the top portion 606 to the bottom portion608 of the housing 602. That is, the outer diameter OD corresponding tothe frontal section 609, the outer diameter OD corresponding to themiddle section 610 and the outer diameter OD corresponding to the endsection 611 are equal to one another. The arrangement where the outerdiameter OD of the housing 602 retains the constant value from the topportion 606 to the bottom portion 608 of the housing 602 ensures thedamping device 600 not to require an extra externally mechanical space,so that the damping device 600 is able to be implemented to the sameapparatus (for example, the furniture part) due to no requirement of theextra externally mechanical space.

As shown in FIG. 22, the said damping devices according to each of theembodiments can be implemented in a furniture part 58. Hereinafter, thedamping device 20 implemented in the furniture part 58 is illustrativeof an example. Specifically, the furniture part 58 includes a firstfurniture member 60, a second furniture member 62 and a drivingmechanism. The first furniture member 60, for example, is a first rail(stationery rail) fixed to a cabinet body 60 a. On the other hand, thesecond furniture member 62, for example, is a second rail (sliding rail)movable relative to the first rail, and the second furniture member 62is configured to mount a drawer 62 a. The driving mechanism includes anejection device 64 and a retraction device 66, wherein the secondfurniture member 62 (drawer 62 a) is in a first position P1 (forexample, a closed position) relative to the first furniture member 60(cabinet body 60 a).

Referring to FIG. 22, FIG. 23 and FIG. 24, when the second furnituremember 62 is pressed by a user and displaced from the first position P1to a second position P2 (for example, an over-pressed position shown inFIG. 23) in a first direction D1 relative to the first furniture member60 and the user releases the pressing force, the ejection device 64including an opening spring will provide an opening force, so that thesecond furniture member 62 is moved, in response to the opening force,to a third position P3 (for example, an open position shown in FIG. 24)in a second direction D2 opposite to the first direction D1. That is aso-called self-opening function. During a final step where the secondfurniture member 62 is pushed by the user to be moved from the thirdposition P3 to approach the first position P1 in the first direction D1relative to the first furniture member 60, the retraction device 66including a closing spring provides a closing force, so that the secondfurniture member 62 is moved to the first position P1. That is aso-called self-closing function. Since the self-opening function and theself-closing function are well-known by one of ordinary skill in theart, the detailed description is omitted herein for simplicity. On theother hand, by a relative motion between the piston 24 (or the extendingmember 26) and the housing 22 of the damping device 20 is able toprovide a damping effect to the second furniture member 62 during aprocess where the second furniture member 62 is moved toward the firstposition P1 in response to the closing force.

A curve diagram of the damping force according to the first condition isshown in FIG. 25, wherein the vertical axis represents a force in Newton(N), and the horizontal axis represents a distance in millimeter (mm).

For example, when the second furniture member 62 is moved from the thirdposition P3 toward the first position P1 in the first direction D1 usingthe damping device 20 for providing the damping force, according to thesaid first condition (this part can be referred to FIG. 7 and FIG. 8),the fluid of the damping medium can flow out from the passage openingsE1 of the passages 48 of the base 28, and reach the zone of the firstside 24 a of the piston 24 through the passages 50 of the piston 24.Therefore, during a process where the damping force D reaches a maindamping zone B2 from a pre-damping zone B1 (as the said pre-dampingstate) which is in front of the first position P1, the damping force Dis able to substantially retain the same in response to the first force(for example, the closing force of the retraction device 66) exerted tothe second furniture member 62. In other words, the damping device 20can provide the first damping effect before the second furniture member62 reaches the first position P1, so as to decrease a velocity of thesecond furniture member 62 before reaching the first position P1.Besides, an over-pressed zone B3 is defined between the first positionP1 and the second position P2.

Otherwise, when the second furniture member 62 is moved from the thirdposition P3 toward the first position P1 in the first direction D1 andthe damping force is provided by the damping device 20, according to thesaid second condition (this part can be referred to FIG. 9 and FIG. 10),the control member 30 is capable of closing the portion or the allportions of the passages 50 of the piston 24, so as to control the flowrate of the damping medium passing through the passages 50 of the piston24 from the zone of the second side 24 b to the zone of the first side24 a of the piston 24. Therefore, as shown in FIG. 26, during theprocess where the damping force D reaches the main damping zone B2 fromthe pre-damping zone B1 in front of the first position P1, the dampingforce D will rise greatly in response to the second force (for example,a continual excessive force exerted by the user to the second furnituremember 62). In other words, the damping device 20 can provide the seconddamping effect before the second furniture member 62 reaches the firstposition P1, so as to rapidly decelerate the second furniture member 62.

Otherwise, when the second furniture member 62 is moved from the thirdposition P3 toward the first position P1 in the first direction D1 andthe damping force is provided by the damping device 20, according to thesaid third condition (this part can be referred to FIG. 9 to FIG. 12),the control member 30 is capable of closing the portion or the allportions of the passages 50 of the piston 24, so as to control the flowrate of the damping medium passing through the passages 50 of the piston24 from the zone of the second side 24 b of the piston 24 to the zone ofthe first side 24 a. Besides, when the second force exerted to thesecond furniture 62 (for example, an instant excessive force exerted tothe second furniture member 62 by the user) decreases to a certaindegree, the resilient member 32 releases the resilient force to thecontrol member 30, and the control member 30 departs from thepredetermined position X and no longer closes the passages 50 of thepiston 24. Therefore, the second damping effect is switched to the thirddamping effect with the weaker damping force. Accordingly, as shown inFIG. 27, during the process where the damping force D reaches the maindamping zone B2 from the pre-damping zone B1 in front of the firstposition P1, the damping force D will rise greatly in response to thesecond force, and the damping force D decreases rapidly before thesecond furniture member 62 reaches the first position P1.

Thereby, the damping device 20 is capable of providing damping effectswith different degree according to various external forces. When aninstant pushing force toward the first direction D1, exerted by the userduring the process where the second furniture member 62 is moved fromthe third position P3 relative to the first furniture member 60, isexcessive, by the second or the third damping effect provided by thedamping device 20 will decrease the force exerted to the secondfurniture member 62 (drawer 62 a) rapidly, so as to prevent the secondfurniture member 62 (drawer 62 a) from directly passing the firstposition P1 to the second position P2 from the third position P3relative to the first furniture member 60 (cabinet body 60 a). Itprevents the ejection device 64 providing an opening force from anunintentional activation (without intention). That is, during the finalstep where the second furniture member 62 is moved from the thirdposition P3 to the first position P1, it effectively ensures that thesecond furniture member 62 is stopped in the first position P1 by thedamping device 20, so as to enhance the stability and reliability of thedriving mechanism.

Accordingly, the embodiment of the present invention includes followingfeatures:

1. The damping device is able to generate a damping forcecorrespondingly in response to a force (or an external force). Thedamping device can provide at least two damping effects with differentdegree to increase the stability and reliability of the drivingmechanism in use.

2. The control member can depart from the predetermined position and nolonger closes the passages of the piston through the resilient memberreleasing the resilient force and the resilient force being exerted tothe control member.

3. The damping device can be implemented in a furniture part with aself-opening function or with both of a self-opening function and aself-closing function. The damping device can prevent an unintentionalopening resulting from the second furniture member pushed directly fromthe third position (for example, the open position) to the secondposition (for example, the over-pressed position).

4. The inner wall of the housing of the damping device has a pluralityof determined inner diameters, and the determined inner diametersfacilitate the damping device to provide specific damping effects.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the invention. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

What is claimed is:
 1. A damping device, comprising: a housing having aninner wall, a chamber being defined by the inner wall and having adamping medium filled therewith; a piston movable in the chamber of thehousing, the piston comprising at least one passage for allowing thedamping medium to pass through; and a controller arranged in the chamberof the housing, the controller comprising a control member and aresilient member; wherein when the piston is moved relative to thehousing by a damping speed, the control member is moved toward thepassage of the piston or closes a portion or all portions of the passageof the piston in response to the damping speed; wherein when the controlmember closes the portion or the all portions of the passage of thepiston, the control member is capable of controlling an amount of thedamping medium passing through the passage of the piston.
 2. The dampingdevice of claim 1, wherein the resilient member generates a resilientforce to the control member in response to the damping speed, thedamping device further comprises a base movable in the chamber, and thecontroller is disposed between the piston and the base, wherein the baseis connected to the piston via an extending portion, and the controlleris movably mounted on the extending portion.
 3. The damping device ofclaim 1, wherein the piston is moved in the chamber of the housing in asubstantially linear direction.
 4. The damping device of claim 1,wherein the resilient member is a disc spring.
 5. The damping device ofclaim 1, wherein the control member defines a space, and the space isfor accommodating the resilient member.
 6. The damping device of claim4, wherein the piston comprises a connecting portion and a contactingportion, the connecting portion and the contacting portion are spaced bya step difference, a base is connected to the connecting portion of thepiston via an extending portion, and the resilient member deformselastically through the step difference.
 7. The damping device of claim1, wherein the control member and the resilient member are integrallyformed as a part.
 8. The damping device of claim 7, wherein the pistoncomprises a connecting portion and a contacting portion, the connectingportion and the contacting portion are spaced by a step difference, abase is connected to the connecting portion of the piston via anextending portion, and the resilient member deforms elastically throughthe step difference.
 9. The damping device of claim 1, furthercomprising an extending member movable relative to the housing via thepiston, and a portion of the extending member extending out of thechamber.
 10. The damping device of claim 2, further comprising a springfor providing an elastic force to one of the piston and the base. 11.The damping device of claim 1, wherein the inner wall has a first innerdiameter and a second inner diameter from a top portion to a bottomportion of the housing, and the first inner diameter is greater than thesecond inner diameter.
 12. The damping device of claim 11, wherein theinner wall has the first inner diameter, the second inner diameter and athird inner diameter from the top portion to the bottom portion of thehousing, and the second inner diameter is greater than the third innerdiameter.
 13. The damping device of claim 11, wherein the inner wall hasthe first inner diameter, the second inner diameter and a third innerdiameter from the top to the bottom of the housing, and the third innerdiameter is greater than the second inner diameter.
 14. A dampingdevice, comprising: a housing defining a chamber, and the chamber havinga damping medium filled therewith; a piston movable in the chamber; abase movable in the chamber with the piston, and both of the base andthe piston comprising a passage respectively for allowing the dampingmedium to pass through; and a controller located between the passage ofthe base and the passage of the piston.
 15. The damping device of claim14, wherein the base is connected to the piston via an extendingportion, and the controller is movably mounted on the extending portion.16. The damping device of claim 15, wherein the controller comprises acontrol member and a resilient member, when the control member is in apredetermined position, the control member is capable of closing aportion or all portions of the passage of the piston, the resilientmember provides a resilient force corresponding to the predeterminedposition, and when the resilient force is released, the control memberdeparts from the predetermined position.
 17. The damping device of claim15, further comprising an extending member and a spring, the extendingmember being movable relative to the housing via the piston, and thespring being configured to provide an elastic force to one of the pistonand the base.
 18. A furniture part, comprising: a first furnituremember; a second furniture member; an ejection device configured toprovide an opening force for the second furniture member to be moved ina second direction, which is opposite to a first direction, to a thirdposition in response to the opening force when the second furnituremember is moved relative to the first furniture from a first position toa second position in the first direction; a retraction device configuredto provide a closing force for the second furniture member to be movedtoward the first position during a process where the second furnituremember is moved relative to the first furniture member from the thirdposition to the first position in the first direction; and a dampingdevice configured to provide a damping effect during a process where thesecond furniture member is moved toward the first position in responseto the closing force, and the damping device comprising: a housingdefining a chamber, the chamber having a damping medium filledtherewith; a piston movable in the chamber, the piston comprising apassage for allowing the damping medium to pass through; a base movablein the chamber; and a controller located between the piston and thebase, and the controller comprising a control member and a resilientmember; wherein the control member is configured to close a portion orall portions of the passage of the piston; wherein the resilient memberis configured to provide a resilient force for the control member to nolonger close the passage of the piston.
 19. The furniture part of claim18, wherein the base is connected to the piston via an extendingportion, the controller is movably mounted on the extending portion,when the control member is in a predetermined position, the controlmember is capable of closing a portion or all portions of the passage ofthe piston, the resilient member provides the resilient forcecorresponding to the predetermined position, and when the resilientforce is released, the control member departs from the predeterminedposition.
 20. The furniture part of claim 18, wherein the damping devicefurther comprises an extending member and a spring, the extending memberis movable relative to the housing via the piston, the spring isconfigured to provide an elastic force to one of the piston and thebase, and the base comprises a passage for allowing the damping mediumto pass through the base.